Question: Multiply.
Explanation: $12 \times 77$ and $1.2 \times 7.7$ multiply the same digits in the same order. So, the product of both problems will also have the same digits in the same order. Let's multiply $12 \times 77$. Then we can estimate to place the decimal point in the product of $1.2 \times 7.7$. $\begin{aligned} 12&\\ \underline{ \times 77}&\\ 14}\\ 70}\\ 140}\\ \underline{+700}}\\ 924 \end{aligned}$ Let's estimate to place the decimal in $1.2 \times 7.7$. $\begin{aligned} 1.2 \times 7.7 &\approx 1 \times 8\\\\ &\approx 8 \end{aligned}$ Where can we place the decimal in $924$ to get a product close to $8$ ? $9.24 = 1.2 \times 7.7$